CN102045559A - Video decoding device and method - Google Patents

Abstract

The invention provides a video decoding method, which is used for decoding image data encoded according to Huffman Tree, wherein the Huffman Tree corresponds to the corresponding decoding table. The method comprises the following steps of: receiving the image data; reading a microcode corresponding to the video compression standards of the image data, wherein the format of the microcode comprises a leaf format, a whole tree format and a unilateral tree format and the microcode of which the format is the leaf format comprises a to-be-processed data bit field and a decoding field; judging the format of the microcode; if the format of the microcode is the leaf format, reading the corresponding image data according to the to-be-processed data bit field; and decoding the image data according to the decoding field. The invention also provides a video decoding device. In the video decoding device and the video decoding method, a plurality of microcodes are loaded in a storage and the image data can be decoded by selecting the microcode corresponding to the image data, so that the decoding speed is increased and the capacity of the storage is reduced.

Description

Video decoding device and video decoding method

technical field

The present invention relates to video decoding technology, in particular to a video decoding device and a video decoding method.

Background technique

Digital TV is becoming more and more important and popular due to its excellent features such as high picture quality, multi-channel capability, interactivity and editing capability. Among them, the decoding of instant video is an important development project of digital TV. Huffman coding is a commonly used coding method for video coding. Fast decoding of Huffman coding can improve the decoding speed of real-time video.

Currently, the Huffman decoding method is to convert the Huffman tree into multiple subtrees in the circuit. The division of subtree adopts the way of complete tree or unilateral tree. If the complete tree division method is adopted, more memory space in the video decoding device is occupied, but the decoding speed is faster. If the unilateral tree division method is adopted, less storage space is occupied, but the decoding speed is slower.

Contents of the invention

In view of this, it is necessary to provide a video decoding device, which can increase the decoding speed and reduce the memory space in the video decoding device.

In addition, it is also necessary to provide a video decoding method, which can increase the decoding speed and reduce the memory space in the video decoding device.

The video decoding device provided in the embodiment of the present invention is used to decode image data encoded according to the Huffman tree, wherein the Huffman tree corresponds to a corresponding decoding table, including a receiving module, a microcode access module, Judgment module, data processing module and decoding module.

The receiving module is used to receive the image data, wherein the image data is composed of a plurality of Huffman tree data, and includes a complete tree and a unilateral tree. The microcode storage module is used to store the microcode of the video compression standard corresponding to the image data, wherein the microcode is stored according to a certain address sequence according to the decoding table, and the format of the microcode includes leaf, complete tree and unilateral tree, And the microcode whose format is a leaf includes a field for processing data bits and a decoding field. The judging module is used for reading the microcode corresponding to the video compression standard of the image data, and judging whether the format of the microcode is a leaf. The data processing module is used to read the corresponding image data in the receiving module according to the field of processing data digits in the microcode. The decoding module is used to decode the data read by the data processing module according to the decoding field in the microcode when the format of the microcode is a leaf, and output the decoding result.

The video decoding method in the embodiment of the present invention is used to decode the image data encoded according to the Huffman tree, wherein the Huffman tree corresponds to the corresponding decoding table, and the method includes: receiving the image data, wherein the image The data is composed of multiple Huffman tree data, including complete trees and unilateral trees; read the microcode corresponding to the video compression standard of the image data, wherein the microcode is stored in a certain order of addresses according to the decoding table Yes, the format of the microcode includes leaf, complete tree and unilateral tree, and the microcode whose format is a leaf includes a field for processing data digits and a decoding field; judge the format of the microcode; if the format of the microcode is a leaf, then Reading the corresponding image data according to the field of processing data bits; and decoding the image data according to the decoding field of the microcode.

The above-mentioned video decoding device and decoding method load a variety of microcodes in the memory of the video decoding device, select the microcode corresponding to the image data to decode the image data, increase the speed of decoding and reduce the time spent in the video decoding device. capacity of the memory.

Description of drawings

FIG. 1 is a block diagram of an embodiment of a video decoding device of the present invention.

FIG. 2 is a flowchart of an embodiment of a video decoding method of the present invention.

Detailed ways

Please refer to FIG. 1 , which is a block diagram of a video decoding device 10 of the present invention. In this embodiment, the video decoding device 10 is used to decode image data encoded according to the Huffman tree, where different video compression standards correspond to different decoding tables.

In this embodiment, the video decoding device 10 includes a receiving module 110 , a microcode storage module 120 , a judging module 130 , a data processing module 140 and a decoding module 150 .

The receiving module 110 is used for receiving image data. In this embodiment, the image data is composed of a plurality of Huffman tree data according to the video compression standard. In this embodiment, after the image data is processed by the video decoding device 10, one Huffman tree data is converted into multiple Huffman tree data, and stored in the receiving module 110, wherein the Huffman tree includes a complete tree and Unilateral tree.

The microcode storage module 120 is used for storing microcodes, wherein the microcodes are used to control the video decoding device 10 to decode image data, and are stored in a certain order of addresses according to the decoding table in the video compression standard.

The microcode is composed of multiple bits of binary code, and there are three formats in total, corresponding to the leaves of the Huffman tree, the complete tree and the one-sided tree. In this embodiment, the microcodes of the three formats all include 22 bits ranging from 0 to 21, wherein the 21st to 20th bits indicate the field of the format represented by the microcode. For example, if the 21st to 20th bits are "10", it means that the microcode format is a leaf; if the 21st to 20th bits are "00", it means that the microcode format is a complete tree; if the 21st to 20th bits If it is "01", it means that the microcode format is a unilateral tree.

Please refer to Table 1, which shows an embodiment of the microcode format corresponding to the leaves of the Huffman tree. In addition to the 21st to 20th bits indicating the format represented by the microcode, the microcode representing the leaf also includes other fields, such as the field for processing data digits, the decoding field, the mode field, the end field, and the replacement decoding Table fields, reserved fields, etc.

Table 1 Microcode format of leaves

bit 21～20 19～17 16～5 4～3 2 1 0 field Format Processing data bits decode model Finish Replace the decoding table

In this embodiment, each field is represented by several bits. For example, the 19th to 17th bits represent the field of the number of digits of the processed data, which represent the number of image data digits to be processed in the receiving module 110, and Huffman related to the depth of the tree. The 16th to 5th bits represent the decoded field, which means decoding the image data, the 4th to 3rd bits represent the field of the mode defined in the video compression standard, different modules represent different calculations for subsequent processing, and the 2nd bit The end field indicates whether the video data has been decoded. The 1st bit is the field of replacing the decoding table, indicating whether the decoding table needs to be replaced when decoding the image data, and the 0th bit is a reserved field, which is currently empty for future further needs.

Please refer to Table 2, which shows an embodiment of the microcode format corresponding to the complete tree of the Huffman tree. In addition to the 21st to 20th bits indicating the format represented by the microcode, the microcode representing the complete tree also includes other fields, such as a field for processing data bits, a depth field, and a compensation value field.

Table 2 The microcode format of the complete tree

bit 21～20 19～17 16～14 13～7 6～0 field Format Processing data bits depth Compensation value

In this embodiment, each field is represented by several bits. For example, the 19th to 17th bits are fields for processing data bits, indicating the number of image data bits to be processed in the receiving module 110, and the Huffman tree It means that the 16th to 14th bits are the depth field, indicating the depth value of the complete tree, and the 13th to 7th bits are the compensation value field. The compensation value in this field is determined by the video compression standard and decoding table. 0-bit reserved field, currently empty.

Please refer to Table 3, which shows an implementation manner of the microcode format of the unilateral tree corresponding to the Huffman tree. In addition to the 21st to 20th bits indicating the format represented by the microcode, the microcode representing the unilateral tree also includes other fields, such as the field for processing the number of data bits, the depth field, the compensation value field, and the matching value field .

Table 3 Microcode format of unilateral tree

bit 21～20 19～17 16～14 13～7 6～0 field Format Processing data bits depth Compensation value match value

In this embodiment, each field is represented by several bits. For example, the 19th to 17th bits are fields for processing data bits, indicating the number of image data bits to be processed in the receiving module 110, and the Huffman tree Depth-related, the 16th to 14th bits are the depth field, indicating the depth value of the unilateral tree, the 13th to 7th bits are the compensation value field, the compensation value in this field is determined by the video compression standard and decoding table, the 6th to 0th Bits represent a field of matching values, which are used for matching with image data. In this embodiment, the matching value is a string of binary numbers, the number of bits may be 7, and the size of the matching value is defined by the video compression standard. In this embodiment, the microcode storage module 120 stores microcodes supporting multiple video compression standards, and users can select microcodes in different formats according to different video compression standards.

The judging module 130 is used for reading the microcode corresponding to the video compression standard of the image data from the microcode storage module 120 and judging the format of the microcode. In this embodiment, the judging module 130 judges the format of the microcode according to the format field in the microcode.

The data processing module 140 processes the data in the corresponding image data according to the field of processing data bits in the format of the microcode. In this embodiment, if the format of the microcode indicates a leaf, the data processing module 140 sequentially reads the n-bit data in the image data according to the values in the 19th to 17th bits of the microcode. In this embodiment, the value of the value in the microcode's processing data bit field is determined by the depth of the Huffman tree and the decoding table.

The decoding module 150 is configured to decode the image data read by the data processing module 140 according to the decoding field in the microcode when the format of the microcode is a leaf, and output the decoding result.

In this embodiment, the data processing module 140 is further configured to delete the image data read by the receiving module 110 according to the value of the processed data bit field in the microcode after the decoding module 150 decodes the image data.

In this embodiment, the judging module 130 is also used to judge whether the decoding of the image data is completed according to the end field. If the decoding of the video data has not been completed, the judging module 130 is also used to judge whether it is necessary Replace the decoding table. If the decoding table needs to be replaced, the video decoding device 10 decodes the image data according to the replaced decoding table until all the image data are decoded. In this embodiment, if the replacement decoding table field of the microcode is "1", it indicates that the image data needs to replace the decoding table, and if the replacement decoding table field of the microcode is "0", it indicates that the video If the data does not need to change the decoding table, the decoding device 10 continues decoding according to the previous decoding table.

In this embodiment, the data processing module 140 is also used to read the n-bit data in the image data in the receiving module 110 according to the field of processing data bits in the microcode when the format of the microcode represents a complete tree. In this embodiment, the value of n is the same as the value of the depth field in the microcode.

In this embodiment, the video decoding device 10 further includes a calculation module 160 for determining the value of the compensation value field in the microcode according to the image data of the complete tree and the corresponding decoding table. The calculation module 160 is also used to determine the address of the next microcode according to the address of the microcode and the value of the image data and the compensation value read by the data processing module 140 . In this embodiment, the calculation module 160 calculates the address of the next microcode as follows: the current address of the microcode+compensation value+the value of the image data read by the data processing module 140=the address of the next microcode address.

In this embodiment, the data processing module 140 is also used to delete the image data that has been read in the receiving module 110 according to the field of processing data digits in the microcode, and the judging module 130 reads the next microcode and continues to judge the next microcode. code format. In this embodiment, the number of bits n of the image data deleted by the data processing module 140 is the same as the value of the depth field in the microcode. In this embodiment, when the judging module 130 judges that the microcode format is a unilateral tree, the data processing module 140 reads the n in the image data in the receiving module 110 in order according to the field of the number of processed data bits in the microcode. bits of data. In this embodiment, the value of n is the same as the value of the depth field in the microcode.

In this embodiment, the calculation module 160 is further configured to determine the value in the compensation value field in the microcode according to the image data of the unilateral tree and the corresponding decoding table.

In this embodiment, the video decoding device 10 further includes a matching module 170 for matching the unilateral tree image data read by the data processing module 140 according to the depth field in the microcode and the video compression standard. In this embodiment, the method for matching the image data with the matching value is: match the image data with the N bits on the right side of the matching value, and judge the image data of the unilateral tree and the N bits on the right side of the matching value from left to right. Consecutive identical digits among the N digits are the matching result, wherein the size of N is the same as the depth of the unilateral tree.

In this embodiment, the calculation module 160 is further configured to determine the address of the next microcode according to the matching result, the compensation value field of the microcode, and the address of the microcode. In this embodiment, the calculation module 160 calculates the address of the next microcode as follows: the current address of the microcode+compensation value+matching result=the address of the next microcode. In this embodiment, the judging module 130 reads the next microcode according to the address of the next microcode, and continues to judge the format of the next microcode.

In this embodiment, the data processing module 140 is further configured to delete the image data read by the receiving module 110 according to the field of the number of processed data bits in the microcode. In this embodiment, the number of bits n of the image data deleted by the data processing module 140 is the same as the value of the depth field in the microcode.

In the embodiment of the present invention, the video decoding device 10 stores microcodes of different video compression standards in the microcode storage module 120, and when the image data needs to be decoded, the microcode access module 120 reads the The video decoding device 10 decodes the image data according to the microcode corresponding to the video compression standard, so as to increase the decoding speed and reduce the capacity of the memory in the video decoding device 10 .

Please refer to FIG. 2 , which is a flow chart of an embodiment of the video decoding method of the present invention. In this embodiment, the method is implemented by controlling the mutual operation of various modules of the video decoding device 10 shown in FIG. 1 through a microcode.

In step S200, the receiving module 110 receives image data. In this embodiment, the image data is composed of a plurality of Huffman tree data according to the video compression standard. In this embodiment, after the image data is processed by the video decoding device 10, one Huffman tree data is converted into multiple Huffman tree data, and stored in the receiving module 110, wherein the Huffman tree includes a complete tree and Unilateral tree.

In step S202, the judging module 130 reads the microcode corresponding to the video compression standard of the image data from the microcode storage module 120, wherein the microcode is stored in the microcode at a certain address according to the decoding table in the video compression standard storage module 120. In this embodiment, there are three formats of the microcode, which are the leaves of the Huffman tree, the complete tree and the unilateral tree.

In step S204, the judging module 130 judges the format of the microcode. In this embodiment, the judging module 140 judges the format of the microcode by judging the format field of the microcode. If the format field of the microcode is "10", the judging module 140 judges that the format of the microcode is a leaf.

In step S206 , the data processing module 140 sequentially reads the n-bit data in the image data according to the value in the field (19th-17th bits) of the processed data bits of the microcode.

In step S208, the decoding module 150 decodes the image data according to the decoding field of the microcode. In this embodiment, the decoding mode and the decoding table are specified according to the corresponding video compression standard.

In step S210, the data processing module 140 deletes the image data read by the receiving module 110 according to the processing data field in the microcode.

In step S212, the judging module 130 judges the end field in the microcode to determine whether the decoding of the image data is finished.

If not, then in step S214, the judging module 130 judges whether the image data needs to replace the decoding table according to the replacement decoding table field of the microcode.

If it is finished, then in step S216 , the video decoding device 10 replaces the decoding table and continues to decode the image data until all the image data are decoded.

If the image data does not need to replace the decoding table, return to step S204, and the judging module 130 continues to judge the format of the next microcode.

If the format field of the microcode is "00", it means that the microcode format is a complete tree, then in step S218, the data processing module 140 processes the data bit field (the value in the 19th to 17th bits) according to the microcode Read the n-bit data in the image data sequentially.

In step S220, the calculation module 160 determines the value of the compensation value field in the microcode according to the image data of the unilateral tree and the corresponding decoding table.

In step S222 , the calculating module 160 determines the address of the next microcode according to the address of the microcode and the value and compensation value of the image data read by the data processing module 140 . In this embodiment, the calculation module 160 calculates the address of the next microcode as follows: current address of the microcode+compensation value+value of image data read by the data processing module 140=address of the next microcode.

In step S224, the data processing module 140 deletes the image data read by the receiving module 110 according to the processed data bit field, and the judging module 130 reads the next microcode, and continues to judge the format of the next microcode.

If the format field of the microcode is "01", then the microcode format is a unilateral tree, then in step S226, the data processing module 140 processes the data according to the field of the microcode (the value in the 19th to 17th bits) ) sequentially read the n-bit data in the image data.

In step S228, the calculation module 160 determines the value of the compensation value field of the microcode according to the image data and the corresponding decoding table.

In step S230, the matching module 170 matches the image data with the matching value according to the depth field of the microcode and the video compression standard, and outputs the matching result. In this embodiment, the method for matching the unilateral tree data with the matching value is: match the unilateral tree data with the N bits on the right side of the matching value, and judge the image data and the right side of the matching value from left to right Consecutive identical digits among the N digits are the matching result, wherein the size of N is the same as the depth of the unilateral tree.

In step S232, the calculation module 160 determines the address of the next microcode according to the matching result, the compensation value and the address of the microcode. In this embodiment, the calculation module 160 calculates the address of the next microcode as follows: the current address of the microcode+compensation value+matching result=the address of the next microcode. In this embodiment, the judging module 130 reads the next microcode according to the address of the next microcode, and returns to step S204 to continue judging the format of the next microcode.

In step S234, the data processing module 140 deletes the image data read by the receiving module 110 according to the number of processed data bits in the microcode, and the judging module 130 reads the next microcode, and continues to judge the format of the next microcode.

In the video decoder 10 and its decoding method provided in the embodiment of the present invention, the image data is converted into a unilateral tree and a complete tree, and then the judging module 130 reads the video compression data in the microcode storage module 120 and the image data. The microcode corresponding to the standard, and the judgment module 130 judges the format of the microcode to realize the decoding of the image data. The present invention combines the advantages of unilateral tree decoding and complete tree decoding, improves the decoding speed and reduces the memory space in the video decoding device 10 .

Claims (20)

1. a video decoder is used for the image data that carries out digital coding according to Hofman tree is decoded, and the corresponding corresponding decoding table of wherein said Hofman tree is characterized in that described video decoder comprises:

Receiver module is used to receive described image data, and wherein, described image data is that a plurality of Hofman tree data are formed, and comprises complete tree and monolateral tree;

The microcode memory module, be used to store with state the microcode of the corresponding video compression standard of image data, wherein said microcode is stored according to certain sequence of addresses according to described decoding table, the form of described microcode comprises leaf, complete tree and monolateral tree, and form is to comprise deal with data figure place field and decoding field in the microcode of leaf;

Judge module is used for reading in regular turn and the corresponding microcode of the video compression standard of image data, and judges whether the form of described microcode is leaf;

Data processing module is used for reading corresponding image data in the described receiver module according to the deal with data figure place field of described microcode; And

Decoder module is used for when the form of described microcode is leaf the decoding field according to described microcode the data that described data processing module read is decoded, and the output decoder result.

2. video decoder as claimed in claim 1 is characterized in that, described form is that the microcode of leaf also comprises pattern field, trailer field and changes the decoding table field.

3. video decoder as claimed in claim 1 is characterized in that, described form is field, depth field and the offset field that comprises the deal with data figure place in the microcode of complete tree.

4. video decoder as claimed in claim 3 is characterized in that, described data processing module also is used for form at described microcode when being complete tree reads corresponding image data according to the field of the deal with data figure place of microcode.

5. video decoder as claimed in claim 4 is characterized in that, described data processing module also is used for deleting the image data that described receiver module has read.

6. video decoder as claimed in claim 5 is characterized in that, also comprises computing module, the value of the offset field that is used for determining described microcode according to the depth field and the corresponding decoding table of described microcode.

7. video decoder as claimed in claim 6 is characterized in that, the offset field that described computing module also is used for the value of the image data that read according to the address of described microcode and described data processing module and microcode is determined the address at next microcode place.

8. video decoder as claimed in claim 1 is characterized in that, described form is field, depth field, offset field and the matching value field that comprises the deal with data figure place in the microcode of monolateral tree.

9. video decoder as claimed in claim 8 is characterized in that, described data processing module also is used for reading according to the deal with data figure place field of microcode the corresponding image data of described receiver module when the form of described microcode is monolateral tree.

10. video decoder as claimed in claim 9 is characterized in that, described data processing module also is used for deleting the image data that described receiver module has read.

11. video decoder as claimed in claim 10 is characterized in that, also comprises matching module, is used for according to the depth field and the video compression standard of described microcode described image data being mated to produce a matching result.

12. video decoder as claimed in claim 11 is characterized in that, described computing module also is used for determining according to the address of the offset field of described matching result and described microcode and described microcode the address at next microcode place.

13. a video frequency decoding method is used for the image data that carries out digital coding according to Hofman tree is decoded, the corresponding corresponding decoding table of wherein said Hofman tree is characterized in that described method comprises:

Receive described image data, wherein said image data is that a plurality of Hofman tree data are formed, and comprises complete tree and monolateral tree;

Read and the corresponding microcode of the video compression standard of described image data, wherein said microcode is to store according to certain sequence of addresses according to described decoding table, the form of described microcode comprises leaf, complete tree and monolateral tree, and form is field and the decoding field that comprises the deal with data figure place in the microcode of leaf;

Whether the form of judging described microcode is leaf;

If the form of described microcode is a leaf, then the field according to described deal with data figure place reads corresponding image data; And

Decoding field according to described microcode is decoded to described image data.

14. method as claimed in claim 13 is characterized in that, described form is that the microcode of leaf also comprises pattern field, trailer field and changes the decoding table field.

15. method as claimed in claim 14 is characterized in that, described method also comprises:

The image data that deletion has been read according to the deal with data field in the described microcode;

Judge the end of whether decoding of described image data according to trailer field;

If described image data is not finished decoding, then judge whether needs replacing decoding table according to changing the decoding table field; And

If do not need to change decoding table, then read next microcode.

16. method as claimed in claim 15 is characterized in that, described method also comprises: if described image data need be changed decoding table, then change decoding table, and continue decoding and finish until the image data decoding.

17. method as claimed in claim 13 is characterized in that, described form is field, depth field and the offset field that comprises the deal with data figure place in the microcode of complete tree.

18. method as claimed in claim 17 is characterized in that, described method also comprises:

If the form of described microcode is complete tree, read corresponding image data according to the field of the figure place of deal with data described in the described microcode;

Determine the value of the offset field of described microcode according to described image data and corresponding decoding table;

Determine the address at next microcode place according to the address at described offset and described image data and described microcode place; And

The image data that deletion has been read according to the deal with data field in the described microcode, and continue to judge next microcode.

19. method as claimed in claim 13 is characterized in that, described form is field, depth field, offset field and the matching value field that comprises the deal with data figure place in the microcode of monolateral tree.

20. method as claimed in claim 19 is characterized in that, described method also comprises:

If the form of described microcode is monolateral tree, read corresponding image data according to the field of the figure place of deal with data described in the described microcode;

Determine the value of the offset field of described microcode according to described image data and corresponding decoding table;

Depth field and video compression standard according to described microcode mate to produce a matching result described image data;

Determine the address at next microcode place according to the address of the offset field of described matching result and described microcode and described microcode; And

The image data that deletion has been read according to the deal with data field in the described microcode, and continue to judge next microcode.

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